Portion of a boot upper



FIG. 1 is a left side elevational view of a portion of a boot upper, showing my new design;

FIG. 2 is a right side elevational view thereof; and,

FIG. 3 is a rear elevational view thereof.

The broken lines shown on the bow are intended to disclaim the interior portions of the bow. The broken lines illustrating the boot are only for context and form no part of the claimed design. 

CLAIM The ornamental design for a portion of a boot upper, as shown and described. 